Multimodal Deep Learning for Remote Stress Estimation Using CCT-LSTM

Stress estimation is key to the early detection and mitigation of health problems, enhancing driving safety through driver stress monitoring, and improving human-robot interaction efficiency by adapting to user's stress levels. In this paper, we present a novel method for video-based remote stress estimation and categorization, which involves two separate experiments: one for stress task classification and another for multilevel stress classification. The method combines two deep learning approaches, the Compact Convolutional Transformer (CCT) and Long Short-Term Memory (LSTM), to form a CCT-LSTM pipeline. For each modality (facial expression and rPPG), a CCT model is used to extract features, followed by an LSTM block for temporal pattern recognition. In stress task classification, T1, T2, and T3 tasks from the UBFC-Phys dataset are used, utilizing sevenfold cross-validation. The results indicated a mean accuracy of 83.2% and an F1 score of 83.4%. For multilevel stress classification, the control (lower stress) and test (higher stress) groups from the same dataset were used with fivefold cross-validation, achieving a mean accuracy of 80.5% and an F1 score of 80.3%. The results suggest that our proposed model surpasses existing stress estimation methods by effectively using multimodal deep learning and the CCT-LSTM pipeline for precise, non-invasive stress detection and categorization, with applications in health monitoring, safety, and interactive technologies.